CaCO3改性对提高MgO基CO2吸附剂循环稳定性的影响  

Effect of CaCO3 modification on improving cycle stability of MgO-based CO2 adsorbents

作　　者：柳春杰 吴素芳[1] LIU Chun-jie;WU Su-fang(College of Chemical and Biological Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江大学化学工程与生物工程学院,浙江杭州310027

出　　处：《高校化学工程学报》2020年第3期742-748,共7页Journal of Chemical Engineering of Chinese Universities

摘　　要：为了提高碱金属盐修饰的MgO基CO2吸附剂的吸附循环稳定性,采用添加CaCO3的方法进行改性。分别以碱式碳酸镁和柠檬酸镁作为前驱体制备MgO,与采用尿素水解沉积法制备的CaCO3混合,并浸渍碱金属盐制备一系列不同CaCO3含量的改性MgO基吸附剂。通过热重分析仪(TGA)考察CO2的吸附性能。结果表明,当吸附气体含40%CO2、CaCO3质量分数为5%时,吸附剂的初次吸附容量可达0.63 g·g^-1,且在20次循环后,吸附容量仍可达到0.50 g·g^-1。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)等方法对吸附剂进行表征分析发现,活性组分MgO的颗粒越小,吸附剂的吸附性能越好;且CaCO3的添加能在一定程度上限制碱金属盐的高温下流动,从而提高吸附剂的吸附循环稳定性。In order to improve the adsorption cycle stability of alkali metal salt-modified MgO-based C02 adsorbents,CaCO3 was used for its modification.MgO was prepared using basic magnesium carbonate and magnesium citrate as precursors,mixed with CaCO3 from urea hydrolysis deposition,and impregnated with alkali metal salt to prepare a series of MgO-based adsorbents modified with CaCO3.The adsorption performance of CO2 was investigated by a thermo gravimetric analyzer(TGA).The results show that when the gas contains 40% CO2 and content 5% of CaCO3 was added,the initial adsorption capacity of the adsorbent can reach 0.63 g·g^-1,and the adsorption capacity can still reach 0.50 g·g^-1 after 20 cycles.Scanning electron microscope(SEM) and X-ray diffractometer(XRD) were used to characterize the adsorbents.The adsorption performance was better with smaller particles of active component MgO.The addition of CaCO3 can limit the flow of the alkali metal salt at a high temperature,thereby improving the adsorption cycle stability of the adsorbents.

关 键 词：MgO基吸附剂 碱式碳酸镁 CACO3 循环稳定性 

分 类 号：TQ115[化学工程—无机化工]